Based on successful collaboration of Dr. L. Huang with the investigators at the University of Michigan, a liposome/DNA core will be established at the University of Pittsburgh to support the gene therapy work at Michigan. The core will perform both service and research roles. Approximately 20 different cationic liposome formulations are available in the core. The cells to be used in the individual gene therapy projects will be sent to the core and tested on these formulations for efficacy of gene transfer using marker gene constructs. If necessary, optimization for the choice of liposome formulation, liposome/DNA ration, and other parameters of the transfection protocol will be performed. The optimized reagent and protocol will then be used by the investigators in the individual projects. In addition, the core will perform research on the gene transfer of human melanoma cells. Melanotropin and various monoclonal antibodies to human melanoma will be directly attached to the cationic liposomes, or indirectly via a polylysine spacer. These antibody targeted liposomes will be used to test the gene transfer activity and specificity of melanoma cells in vitro. They will also be directly injected into melanoma tumor grown in the nude mice. Enhanced tumor cell transfection and reduced release f the transgene into the systemic are expected with these targeted vectors.